Albert Barnes Commentary Nehemiah 11:21

"But the Nethinim dwelt in Ophel: and Ziha and Gishpa were over the Nethinim." — Nehemiah 11:21 (ASV)

Ophel, the southern spur of the temple hill, having a wall of its own (Nehemiah 3:27), might be reckoned either in Jerusalem or outside it. Here it is made a separate place.